Thursday, April 29, 2010

Glycerol Injections

Glycerol injections offer a low-risk surgical option to patients suffering from trigeminal neuralgia. Glycerol injections are one example of a rhizotomy; that is, a surgical procedure during which selected nerves are damaged to stop pain. Typically, the outpatient procedure is very straightforward: a needle is inserted through the skin (in the cheek, next to the mouth) into the trigeminal nerve near the base of the skull. This is the place where the three parts of the nerve come together and exits the skull. Doctors use an x-ray to confirm that the needle is in place, then they inject a small amount of glycerol, which damages the nerve and thus blocks the pain signal. Throughout the short process (it takes only a few minutes), the patient is sedated intravenously.

One very positive aspect of glycerol injections is their almost immediate effects; the glycerol acts quickly and stops nerve activity within a matter of hours. In a study published with the Journal of Neurosurgery by Harold Wilkinson, eighteen patients with trigeminal neuralgia were given sixty injections of 10% phenol, and "eighty-seven percent of injections brought marked or total relief initially." The downside to this procedure, however, is that the pain often returns for many patients. About half of the patients who benefit from glycerol injections will have recurrent pain within three or four years; glycerol injections can be performed more than once, but they are less effective over time (or with increasing number of procedures). In Wilkinson's study, relief lasted for an average of nine months and most patients requested a repeat procedure. Also, "Of those injections that provided initial relief, 37% still provided relief after 1 year and 30% after 2 years."

The logistics of the procedure are obviously very straightforward, and because it is so non-invasive, there are relatively few side effects associated with the surgery. Adverse effects to anesthesia are minimal (because the treatment is administered within such a short time), and other major problems include damage to the wrong nerve, or a failure to access the trigeminal nerve, as well as bleeding from the puncture site. The goal of the x-ray, of course, is to help target the correct nerve and prevent administering the glycerol to the incorrect site. More commonly, most patients experience mild facial numbness and/or tingling as a result of the damaged nerve, but this fades over time (unfortunately, numbness can persist for up to six months, which is not much shorter than the time frame for which the injection may be effective).

But how does the procedure really work? According to the National Institute of Neurological Disorders and Stroke, "The glycerol injection bathes the ganglion (the central part of the nerve from which the nerve impulses are transmitted) and damages the insulation of trigeminal nerve fibers." Glycerol and phenol (glycerol more commonly) are used as sympathetic blocks for nerve signals. On one hand, phenol dissolves nerve fibers and kills the nerve tissue prematurely (a process called "necrosis,") during which the dying cells do not signal to the immune system as normally-dying cells would do, leading to a build-up of dead tissue. This is why the injection is only administered in small amounts and to very specific regions of the nerve. Glycerol also prevents the nerve from producing signals by breaking up the nerve fibers. Over time, the pain may return as the nerve repairs and re-myelinates (coats) itself, although studies on rats indicate that examination of phenol- or glycerol- affected nerves can be morphologically distinguished from healthy nerves.

Friday, April 23, 2010

Biofeedback: What Is It?

According to the National Pain Foundation, biofeedback "allows you to train your mind and body to control or normalize the way you respond to pain. It makes you more aware of your body and helps you learn how to relax and relieve pain." For people whose pain is the result of stress or muscle pressure applied to all the wrong places, biofeedback offers one form of holistic, "alternative" treatment.

In August 2008, Massage Magazine published an article about biofeedback and "brain training:" "The New Generation of Mind-Body Therapies." Basically, these techniques are responses to the theory that problems like hypertension and anxiety disorders can be controlled by our minds. Rather than exclusively functioning from the autonomic nervous system (which operates the unconscious activity within the body, such as breathing and heart rate), scientists recognize the role of conscious regulation as well. Biofeedback is similar to the placebo effect- not in the sense that it is a "hoax," but rather that the mind can affect the body's physical responses.

But how exactly does biofeedback work? The University of Maryland Medical Center states, "Researchers aren't exactly sure how or why biofeedback works." As disheartening or even disconcerting as this may sound, there is nothing involved in biofeedback techniques that could pose any threat to the patient's well-being; the worst result one could expect to experience would be a lack of improvement. Unfortunately, this may be the case for many neuralgia sufferers. Although biofeedback is listed as an alternative treatment for neuralgia, no studies have clearly linked biofeedback as a solution to neuralgia. Generally, the technique is most effective for people with stress-related pain, so biofeedback therapy would only be useful to patients whose pain is a result of elevated blood pressure or muscle strain. Nevertheless, it is something to consider.

The actual therapy process involves learning to control (not completely, but to a much greater extent) bodily processes such as heart rate, blood pressure, and muscle tension. Electrodes are attached to the patient's skin so that these processes (typically muscle tension, skin temperature, or brain wave activity) show up on a monitor, either audibly or visually. The therapist leads the patient through mental exercises (usually intended to relax the person or focus their thoughts) until the patient can learn to identify the mental exercises that trigger desired responses. For example, in the case of urinary incontinence, a person can overcome their loss of bladder control by learning what muscles need to be contracted. For pain or stress, the therapist can use the monitor to detect where a patient is tense, and then pinpoint what thoughts or feelings cause tension. Ultimately, the goal of the session is to help the patient become more aware of processes that normally occur unconsciously, so he or she can react to them consciously.

As stated above, one of the best things about biofeedback is that there are no side effects; however, its usefulness for neuralgia patients is yet to be determined (unless your pain is distinctly stress-related). Although sessions range in technique and length depending on the biofeedback specialist, they are typically shorter than an hour. Some patients claim to see results within 8 weeks (one session per week), but treatment generally requires at least ten weekly sessions- and at least twenty for conditions like high blood pressure. The mental exercises, however, are techniques that the patient can use independently, outside the session. Cost for each session can be anywhere from about $35-$85.

From the University of Maryland Medical Center: "Specialists who provide biofeedback training range from psychiatrists and psychologists to nurses, dentists, and physicians. The Association for Applied Psychology and Biofeedback (www.aapb.org) is a good resource for finding qualified biofeedback practitioners in your area."

Sunday, April 18, 2010

TN and the Myth of Upper Cervical Care?

In 1997, author James Tomasi treated his trigeminal neuralgia with upper cervical chiropractic adjustment and was cured of his pain; he subsequently published the book "What Time Tuesday," detailing his experiences with TN, the pain that almost drove him to suicide, and the procedure that cured him.

According to the NUCCA (National Upper Cervical Chiropractic Association), upper cervical care procedures were developed more than forty years ago and, since that time, have gained popularity within the medical community. Generally, upper cervical corrections involve adjusting the large, first vertebrae of the spinal column, called the "atlas." When misaligned- either from everyday activities over time, or trauma to the neck- the atlas can compress the brainstem and cause pressure where previously there was none. The pain of a misaligned atlas can manifest itself in many different ways, and patients with everything from back pain to indigestion have experienced some positive results with upper cervical correction (UCC). Ideally, when a chiropractor corrects the atlas alignment, he (or she) helps straighten the spinal column and removes pressure on any nerves that the misaligned bone may be pressing.

The procedure seems to offer viability for TN patients because it deals with pressure at the base of the brain, near the brain stem, which is the region more invasive techniques- such as microvascular decompression- address (this is where the trigeminal nerve exits the brain). Yet, it is only recently that TN has been treated with UCC. Why? First, there have not been clinical trials that evaluate the connection between TN and upper cervical corrections, and there are no statistics to gauge the success rates of such procedures for TN patients. Second, there is a lot of political tension between the medical and chiropractic community. Seemingly floating between "alternative" treatments and medical procedures, the niche that chiropracticity has carved for itself is very self-contained; because of this, little advertisement is made for chiropractic treatments. Third, not many TN patients seem to have used UCC to treat their pain, so testimonials are few and far between (except, of course, Tomasi's book). Because of all these reasons, it seems difficult to even offer an opinion as to whether the upper cervical correction is worthwhile. Personally, I would tend to avoid such techniques, but I fully recognize that much of that tendency is simply a result of the doctor-vs.-chiropractor bias. There are many cases in which chiropractors are the only viable option (a misaligned spine, for example), but for many people (myself included), the breadth of symptoms that chiropractors can cure makes it seem more "holistic" and less precise.

But that is not fair to the chiropractic field. The spinal column is a central part of the human anatomy, and its involvement with so many physiological roles means that its negative effects can manifest themselves in many places and many ways. Those who have experienced chiropractic treatment- specifically, UCC- can testify that the process is very thorough, with little guesswork involved (assuming the chiropractor is qualified and by-the-book). There are a number of different techniques to re-align the atlas (which can vary from chiropractor to chiropractor), but many involve the use of a "percussion adjusting instrument" which applies a precise, split-second sound vibration to one end of the atlas (just below the ear). This generates a slight pressure (about 3 lbs) that causes the vibration to move through the atlas to realign it. The instrument itself resembles some kind of power tool- an electric drill, perhaps- but the procedure is painless; the patient only feels a slight pressure like a brief tap or massage. The "stylus" on the instrument (the rod that applies the pressure) can be aimed to a particular degree, based off x-rays taken before the procedure.

There are a lot of positive aspects to UCC: it is painless, eases symptoms almost immediately, and there are few side effects. Although the procedure does not involve any cutting or other invasive techniques, however, it is important that your chiropractor be meticulous and well-qualified. The spinal column, for all its strength, is a delicate instrument, and further damage can create even more drastic problems; for example, pressure to a nerve can increase pain, and pressure to a vessel can cut off blood flow, causing a stroke. The negative aspects of UCC- besides its side effects, which result primarily from negligent chiropractors- include the cost of the procedure over time. Ideally, one would only need to have their atlas corrected once (cost for this includes the cost of x-rays, but varies from chiropractor to chiropractor), but the treatment can also entail repeated visits if the patient continually misaligns his/her spine. Luckily, this can often be avoided with basic preventative measures, such as not falling asleep on the couch or with one's head at an awkward angle. Ultimately, in the search for relief from TN, UCC may be included in the list of possible treatments, particularly as a non-invasive alternative with few side effects. With the low risk, UCC may be a reasonable option to try before surgery.

Sunday, April 11, 2010

How Microvascular Decompression Works

According to the Mayfield Clinic in Cincinnati, Ohio, microvascular decompression (MVD) is one of the most invasive surgeries to treat Trigeminal Neuralgia, vagoglossopharyngeal neuralgia, and hemifacial spasms, but it may actually preserve facial sensation. MVD is an applicable treatment for neuralgia when the nerve pain is caused by compression from a proximal blood vessel; the pulsing of the vessel and its pressure on the nerve causes the nerve to send "bad" messages, translating to pain. MVD is a specific treatment for cranial nerves that is performed by inserting a tiny sponge between the vessel and the nerve at the base of the brainstem. Specifically, for TN, the sponge is placed between the trigeminal nerve and the superior cerebellar artery or a branch of the petrosal vein. The sponge separates the nerve from the pulsing vessel without creating more pressure.

The Mayfield Clinic indicates that the most viable patients for the procedure are those who desire minimal facial numbness (this can result from treatments like glycerol injections), or who experience recurrent pain after other radiosurgeries.

Generally, the procedure is as follows: the surgeon will make a small incision behind the ear (on the side of the face where pain is located), and then a circular opening (about a inch) in the back of the skull, to expose the trigeminal nerve. The surgeon will separate the nerve from the vessel and place a sponge between the two. If the vein is stuck to the nerve, it is cauterized (burnt with electric current to stop blood flow and remove the vessel). If no vessel is visible near the nerve, the surgeon may just sever the nerve. This does not usually happen, however. Typically, the nerve remains undamaged, which is why few patients have facial numbness. Because the bone opening is small enough, it is usually covered by a titanium plate and the skin is stitched back together. Statistics from the Mayfield Clinic say that this procedure is effective for 95% of patients. The major benefit of MVD is that it causes little or no facial numbness. After MVD, 20% of patients have pain recur within 10 years.

The risks that accompany MVD are those typical for any surgery (bleeding, infection, blood clots, and reactions to anesthesia), but risk is also greater because the surgery involves nerves in the brain. There are small chances of decreased hearing, facial weakness, facial numbness, double vision, paralysis, or even death. Often, surgery is a last resort for patients suffering TN or other nerve pain or facial spasms. Although there are many different surgical options, and the invasiveness of MVD makes it a more extreme choice, it has high effectiveness rates and few side effects. Of course, the few side effects that distinguish MVD from other neuralgia operations are dramatic. Most other surgeries dealing with nerve pain result in decreased sensation, and for those who are interested in not only halting their pain, but also preserving sensation, MVD is an option to consider.

Monday, April 5, 2010

Acupuncture as an Alternative Treatment

In March 2008, Peter Valaskatgis published a case study concerning a 72-year old female suffering from post-herpetic neuralgia and atrial fibrillation (AF). Over a period of four months, the woman underwent two series of acupuncture treatments (20 treatments in four months. Although the authors state that "further studies are warranted to explore these observations of a possible effect of acupuncture on both atrial fibrillation and post-herpetic neuralgia" (abstract), they also report that the woman experienced pain levels reduced by 67%.

On their website, the National Pain Foundation has stated, "Little quality research has been done to accurately reflect the benefit of acupuncture for treating TN but it can be effective for some people." Indeed, many patients have experienced positive results with acupuncture for all kinds of pain, including neuralgias. However, it is important to note that, at the very least, most patients continue taking medications- at a reduced dosage- or herbal supplements to complement the acupuncture procedures. Today, the problems between acupuncture and modern medicine are the fundamental understandings of the body that guides each practice. Acupuncture originated in China and involves placing long, thin needles into areas of the body where bad health occurs. To an acupuncturist, these health problems arise from a blocked "channel" within the body, through which energy, or "qi" normally flows.

Typical acupuncture procedures involve the insertion of anywhere between one and twenty needles into the body. The needles may just break the surface, or be inserted into the skin by several inches (obviously, longer needles are inserted into deeper layers of muscle/fat, or along the skin just beneath the surface). The location of the needles is entirely dependent on the pain the patient is experiencing, although there are several established insertion points for patients suffering neuralgia. Usually, the needles are left in the body for 15 to 30 min, but sometimes they are removed after only a few seconds. For a stronger effect, or with patients who have more persistent pain, the needles are warmed or electrically charged—don’t worry, though! This occurs after the needles have been inserted and produces no additional pain.

The NIH has concluded that “adverse side effects of acupuncture are extremely low and often lower than conventional treatments.” For every 10,000 procedures, it is estimated there are 671 cases of adverse effects, including: bleeding, bruising, dizziness, fainting, nausea, and increased pain (all typically minor). Although acupuncture is technically an “invasive” procedure because it involves needles, few patients experience sensations stronger than tingling. The needles are much thinner (and safer) than a typical hypodermic needle because they are not hollow; they also come to a smoother point. In the U.S., needles must be sterilized and can only be used once. Also, there are styles of Japanese acupuncture that never actually penetrate the skin. Generally fees range from $60-120 per session. The initial treatment is usually longer and more comprehensive and usually costs more, and often discount prices are available for “package” treatments. For more price details, see http://www.costhelper.com/cost/health/acupuncture.html

Although there is no data to refute or support the hypothesis (Cheng 2009), it is generally believed that acupuncture works by locally stimulating the affected nerve. Studies with animals have demonstrated increased blood flow in nerves by acupuncture, presumably helping the nerve heal or prevent it from overcompensating for a lack of sensation (Cheng, Neuroanatomical Basis of Acupuncture Treatment for Some Common Illnesses). For muscle pain, studies show that acupuncture needles stimulate nerve fibers in the muscle and cause minor tissue damage that triggers a local healing response, including blood flow (Cheng 2009). Unfortunately, no mechanism has been likewise established for pain that is exclusively associated with a nerve.

Basically, the American Academy of Medical Acupuncture states that at least one study has indicated the success of acupuncture in treating neuralgias. However, the benefits are inherently difficult to test scientifically because there is no easy reconciliation between the concept of "energy levels" that guides acupuncture and the Western understanding of nerve mechanisms. Additionally, it is hard to create tests that are “controlled,” because acupuncture administration is so dependent on the patients’ pain sensation. Regardless, many people have experienced pain relief from acupuncture, over the course of several treatments (some physicians attribute this to the placebo effect, and indeed there is a large association between acupuncture and mental health, but again no link has been substantiated). If you are considering acupuncture, the primary considerations you must remember are: check that your acupuncturist is well-trained, with credentials, and will be using sterile needles. Initially, you would probably not need electrical or heat stimulation, but your acupuncturist’s decision to use either treatment immediately is certainly not indicative of a bad procedure.